1. Field of the Invention
The present invention relates to a knitted fabric of a multi-layered structure made of non-hygroscopic fiber yarn, such as synthetic fiber yarn, but excellent in water-permeability and water-diffusibility. More specifically, the present invention relates to a knitted fabric suitable for making sports wear having good sweat-removal ability, heavy duty durability, aesthetic appearance, and wash-and-wearability.
2. Description of the Prior Art
Fabrics utilized for sportswear such as sportsshirt, warm-up suits, sweatsuits, and sports-pants preferably feature good elasticity and light weight for easy wearer movement. Knitted fabrics, therefore, command a large share of the sportswear market.
Knitted fabrics utilized for sportswear include fabrics of 100% natural fiber yarn, such as cotton or wool, 100% synthetic fiber yarn, such as polyester or polyamide, and combinations of natural and synthetic fiber yarn.
Since sportswear is often worn directly on a wearer's body, which gives off considerable sweat during sports activity, sportswear must be able to easily absorb sweat and transfer it to its outer surface for evaporation in the open air. Sportswear must also withstand heavy duty wear and has a characteristic of wash and wear for frequent laundering.
Up until now, no fabric has possessed all of the above-mentioned properties. For example, 100% natural fiber yarn fabric can absorb sweat well due to its excellent hygroscopic property, but cannot quickly transfer it outside for evaporation therefrom. Moreover, after laundering, it holds a considerable amount of water even after spin-drying, thus needs much time for complete drying.
Conventional 100% synthetic fiber yarn fabric, on the other hand, has good wash-and-wearability, but imparts an uncomfortable wet feeling to the wearer because the secreted sweat remains on the wearer's skin and/or inner surface of the fabric due to its poor water-absorbing speed.
A fabric composed of mixed spun yarn or mixed filament yarn or a fabric composed of yarns consisting of natural fiber and synthetic fiber yarns has a fair wash-and-wearability, but the wash-and-wearability is insufficient for sports wear usage. In addition, natural fiber and synthetic fibers have different physical and chemical properties, especially in dyeability or thermal properties. Therefore, uniform dyeing and complete heat-setting of the above-mentioned fabric composed of the both fibers cannot be obtained.
Japanese Examined Utility Model Publication (Kokoku) No. 56-23282 discloses a quilted diaper comprising a sheet composed of an ultra-fine fiber having a fineness within a range of from 0.01 to 0.5 denier. The sheet is covered with a fabric composed of a course fiber having a fineness within a range of from 1 to 5 denier over both sides thereof. Japanese Unexamined Patent Publication (Kokai) No. 52-25168 proposes an absorbent fabric having an intermediate layer of ultrafine fibers of less than 0.7 denier covered with a surface layer of coarse fiber of more than 1 denier, in which the ratio of fineness between the two fibers is more than 4 and the fiber surfaces are processed by hydrophilic treatment.
The former diaper, however, is aimed only to absorb and hold water in the ultrafine fiber sheet. Therefore, though a wet feeling on the wearer's skin can be avoided because the water is immediately removed from the skin through the surface layer, the water absorbed in the sheet cannot easily evaporate therefrom. Thus, the material of the above diaper is unsuitable for sportswear. In addition, the material is too thick and heavy as well as poor in stretchability due to quilting.
On the other hand, the latter absorbent fabric lacks durability against abrasion, pilling, and snagging because the surface layer is composed of a yarn made from ultrafine fibers of less than 0.7 denier, which are easily damaged by external force applied to the fabric surface. In addition, the fabric has a high water-holding ability due to fine space or void provided among the fibers composed of the yarn or a group of fibers, which is referred as inter-fiber space hereafter in short, formed in the fine fiber layer. Therefore, though the drying speed of the fabric is superior to that of a natural fiber fabric in which a fiber itself has hygroscopic property, it is still insufficient to fulfill the requirement of so-called `wash and wear` property. Further, the fine fiber of less than 0.7 denier utilized for the above-mentioned fabric, which is preferably manufactured by a process proposed in Japanese Examined Patent Publication (Kokoku) No. 44-18369, is rather expensive and, therefore, is unsuitable for mass-consumption goods such as sportswear.